1. Field of the Invention
The present invention relates to a negative developing method and a negative developing apparatus for performing development to a semiconductor substrate, a glass substrate for photomask, a glass substrate for liquid crystal display, an optical disk substrate, and the like (hereinafter, simply referred to as a “substrate”) using developer containing an organic solvent.
2. Description of the Related Art
In recent years, instead of a positive developing method (also called positive tone development), a negative developing method (also called negative tone development or negative development) has been adopted. In the negative developing method, a non-exposed part of a resist film is dissolved. The negative developing method uses developer that contains an organic solvent such as butyl acetate, and a cleaning liquid that contains an organic solvent such as MIBC (Methyl Iso Butyl Carbinol). This is disclosed, for example, in page 79 of Japanese Unexamined Patent Publication No. 2011-28281A. The cleaning liquid used for the negative developing method is more expensive than the cleaning liquid (e.g., deionized water) used for the positive developing method.
Accordingly, Japanese Unexamined Patent Publication No. 2014-135440A has suggested the following. That is, a surface drying step for drying a surface of a substrate is performed after a developing step while a substrate is rotated without a cleaning liquid. Such a method allows reduction in amount of usage of the cleaning liquid.
However, the example of the currently-used apparatus with such a configuration has the following drawback. A line and space pattern has a larger non-exposed part than a hole pattern, leading to a more amount of dissolution product upon forming the line and space pattern. In the developing step, the developer with a more amount of dissolution product causes the dissolution product to adhere to the resist film again even through the surface drying step. This may cause development defect such as bridge defect. In this specification, the term “dissolution product” is collectively used for a dissolved resist film in the developer, and a residue or foreign substances that cause the development defect.